Its really sad people are blowing these DP's off since someone strategically sold his UR DP's and then posted how 3" DP's made more power. There are MANY cars out there that are in the 400+ whp club and in the low 12's and high 11's running 2.5" DP's. You can see that these are ceramic coated and wrapped. I have been running 3" DP's and my butt dyno can not tell the difference.